1. Field of the Invention
The present invention relates to a headlamp of a vehicle, and more particularly, to an automotive headlamp which is structured in a simple manner to secure a sufficient amount of light, emit light in different/various beam patterns, and improve heat dissipation efficiency.
2. Description of the Related Art
Vehicles are typically equipped with various automotive lamps having a lighting function and a signaling function, among others. That is, automotive lamps enable the driver of the vehicle to easily detect objects around and ahead of the vehicle while driving at night or in a dark area. They also inform other vehicles and road users of the vehicle's driving state. For example, a headlamp and a fog lamp are designed for providing light, and a direction indicator, a taillight, a brake light, and a side marker are designed for signaling.
Recently, many automotive lamp manufactures have begun to use halogen lamps or high-intensity discharge (HID) lamps as light sources. Additionally, light-emitting diodes (LEDs) have been used as light sources as well. LEDs have a color temperature of approximately 5500 K which is close to that of sunlight. Thus, LEDs cause the least eye fatigue. In addition, LEDs increase the freedom of lamp design due to their small size and are economical due to their semi-permanent lifespan.
LEDs, in particular, are being introduced to reduce lamp configuration complications and decrease the number of manufacturing processes required to produce a headlamp. In particular, attempts are being made to extend lamp life using characteristics of LEDs. Furthermore, since limited space is not an issue due to the small size of the LEDs, they may be utilized in a plethora of applications.
Of the various types of automotive lamps, a headlamps use more than one beam pattern unlike other types of lamps which typically use only one. For example, the headlamp may emit light in a beam pattern optimum for driving conditions of the vehicle such as travelling speed, travelling direction, road surface conditions, and ambient brightness. In so doing, the headlamp may ensure driver visibility without blinding other vehicle drivers on the road. Generally, one or more LEDs are used to emit light in each beam pattern while securing a sufficient amount of light. However, to emit light in different beam patterns, elements corresponding to each beam pattern are required. Accordingly, this increases the number of parts, costs and space required. In addition, when LEDs are used as light sources of automotive lamps, the light emission efficiency of the LEDs rapidly deteriorate as the temperature rises.
Therefore, a solution that can emit light in various beam patterns, secure a sufficient amount of light, and prevent a temperature rise due to heat emitted from LEDs while reducing the number of parts, costs and space required to emit light in different beam patterns is required.